Tool for slitting two-conductor cable

ABSTRACT

On wide face the tool has a diagonally disposed slot into which a two-conductor cable, heavily insulated and of oval cross section, can be inserted edge first to lie between lead and trailing rollers. Pulling on the handle toward the free end of the cable swings the tool into alignment, thereby piercing the cable with a pointed blade which is carried between the rollers. With continued pulling the leading sharp edge of the blade then slitting the heavy insulation between the two conductors, the angle of the blade edge tending to draw the cable against the lead roller.

ynited States Patent Inventor Robert J. Stuckel 1210 Greenacres Lane, Mount Prospect, lll. 60056 Appl No. 839,942

Filed July 8, 1969 Patented Aug. 24, 1971 TOOL FOR SLITTING TWO-CONDUCTOR CABLE 13 Claims, 5 Drawing F igs.

FORElGN PATENTS ,149 4/1949 Netherlands ABSTRACT: 0n wide face the tool has a diagonally disposed slot into which a two-conductor cable, heavily insulated and of oval cross section, can be inserted edge first to lie between lead and trailing rollers. Pulling on the handle toward the free end of the cable swings the tool into alignment, thereby piercing the cable with a pointed blade which is carried between the rollers. With continued pulling the leading sharp edge of the blade then slitting the heavy insulation between the two conductors, the angle of the blade edge tending to draw the cable against the lead roller.

PATENTEUAUBZMHYI 3500 5305 my IN VE N TOR L K25 ROBERT J. STUCKEL $3040, @4421 & flaw Attorneys TOOL FOR SLITTING TWO-CONDUCTOR CABLE I SUMMARY OF THE INVENTION I The present invention relates to a simple and inexpensive device for slitting an elongated object such as an electrical cable or the like.

DESCRIPTION OF THE DRAWINGS perspective view of an embodiment of the inven- DESCRIPTION OF SPECIFIC EMBODIMENT The following disclosure is offered for public dissemination in return for the grant of a patent. Althoughit is detailed to ensureadequacy and aid understanding, this is not intended to prejudice that purpose of a patent which is to cover each new inventive concept'therein no matter how others may later disguise it by variations in form or additions or further improvements. The claims at the end hereof are intended as the chief aid toward this purpose, as it is these that meet the requirement of pointing out the parts, improvements, or combinations in which the inventive concepts are found.

FIG. 3 illustrates a crosssection of a telephone cable, generally 10, such as might be employed in the. connection from the house to the telephone pole. It comprises a pair of wires 11 and 12, each with is own insulating covering 13 and 14 respectively. An insulating sheath l encompasses the two coverings 13 and '14 and forms a unitary'cable. In some instances a fabric or string reinforcing 'will be positioned between sheath 15 and coverings l3 and 14. This wire'has a width as indicated by the dimension w and a depthas indicated by the dimension d. v l

The embodiment illustrated includes a frame, generally 17,

comprising a backwall 18, a front wall consisting of generally triangular segments I9aand l9b, a bottom wall and a top wall'2l. Wall 18 includes an extension 22 which is welded to a tubular handle 23. The walls 18-21 form a sleeve which defines an internal chamber 25 and end openings 26 and 27. The distal edges of segments 19a and 19 12 define a slot 28 which communicates with both of end openings 26 and 27, the communication with opening 27 being provided in part by the shortness of bottom wall 20 at the-handle end. Slot 28 has a width, indicated by the dimension d in FIG. 2, which is approximately equal to and especially not less than the depth d of the cable but substantially less than the dimension w of the cable, as indicated in FIG. 3. Walls 18 and 19 are spaced apart a dimension w (indicated in FIG. 4) which is approximately equal to but not less than the width w of the cable 10.

A roller 30 is journaled on a rivet 31 extending between walls 18 and 19 a. A roller 32 is journaled on rivet 33 extending between walls 18 and 19b. The walls 18 and 19, together with rollers 30 and 32 define a passageway through the sleeve for the movement of the cable 10 therethrough. A knife blade 34 having a sharpened cutting edge 35 is positioned approximately midway between walls 18 and 19. The knife is centered by a pair of mounting blocks 36 and 37. Block 37 has a recess 38 to receive the shank of knife. 34. A bolt 39 extends through blocks 36 and 37 and knife 34 so as to hold them in place. Bolt 39 has a nut 40 on the end thereof ,so that it can be tightened to clamp the knife 34 securely between blocks 36 and 37.

Assuming that itis desired to slit the cable 10 from one end 10a back a given distance, say, for example, 12 inches, the cable 12 inches from the end would be introduced into chamber 25 inside the sleeve'by passing it through slot 28; The fact that the slot will receive the cable only in one direction,

because ofthe'dimension d,'aids in quickly and accurately achieving proper alignment of the cable in the cutting device. With the point 35a of the cutting edge 35 at a location approximately 12 inches from end 1011 of the cable, the cable is grasped at a location 10b somewhere beyond the device with one hand while the other hand grasps the handle 23. The two hands are now moved away from each other so that there is a relative movement between the cable and the cutting device, which relative movement is such that the cutting device proceeds towards end 10a of the cable.

Asa result of this relative movement, the point 35a initially penetrates the cable, between coverings l3 and 14. As it does so the drag of the knife rapidly forces the knife blade completely, through the cable so that both sidesof sheath 15 are slit along a plane between coverings l3 and 14. Animportant feature of the invention is the inclination of cutting edge 35 with respect to the path along which the cable 10 moves through the device, as best seen in FIG. 2. The edge 35 inclines downwardly and towards the portionof the cable that is moving toward it, i.e. the portion of the cable between edge 35 and end 10a in FIG. 2. The result of this inclination, in conjunction with the positioning of the knife adjacent the support defined by'roller 32 is that the cable moving into the knife edge is in effect wedged between the knife edge androller 32. This wedging action forces-the cable 10 towards roller 32. Thus, the knife is in effect self-penetrating ofthe cable and the arrangement assures that thereafter the cable will remain straddle of the knife.

Another important feature is the offsetting of the'handle 23 with respect to the passageway for the cable through the device. The principal point of resistance to the movement of the cable through the passageway is the drag of knife 34 as it splits and spreads the cable.'Thus, there is a principal line of force between the axis of tubular handle 23 and the point at which the longitudinal axis of cable 10 (the longitudinal axis of the passageway) intersects knife edge 35. This line of force is at an acute angle to the longitudinal axis of the passageway.

. In the disclosed embodiment which was intended for use with a'telephone lead-in cable in which the wires 11 and 12 were copper-coated steel, said offset is about 35. With more flexible cable the offset can be moreand with cable of greaterstiffnessthe offset can advantageously be less. In any event, this acute anglebetween thepositioning of the passageway and the handle axis is importantin obtaining the desired cutting ac.- tion.'

From the foregoing it will be readily apparent that embodiments of the invention can be produced which are inexpensive to manufacture and simpleto operate. The knife and its cutting edge are completely shrouded by walls 18 and 1%. There is extremely little likelihood that a user could accidentally hurt himself on the knife edge or catch the knife on some foreign object which might cause damage. Should the knife edge 35 become dull, it can be easily removed for replacement or sharpening by withdrawing bolt 39 and extracting the knife. The reverse procedure for replacement is likewise easily done. The configuration of the blocks 36 and 37 and of knife 34 is such that the knife cannot be incorrectly assembled in the frame 17.

While a cable in which the wires 11 and 12 have individual insulations l3 and 14 has been illustrated, it will be unmined width and where in the device has a frame,has portions defining a passageway for the cable which portions include first and second portions spaced apart approximately said predetermined depth as measured transversely of the passageway and third and fourthportions spaced apart approximately said predetermined width as measured transversely of the passageway, and has a knife with a cutting edge projecting into said passageway from the one side thereof at which said first portion is positioned and toward the other side thereof at which said second portion is positioned with the knifebeing between said third and fourth portions so that the knife slits the cable while the cable is grasped with one hand and the device is grasped by the other and a relative movement between the two is produced, which movement is longitudinally of the object and in a direction such that the knife moves cutting-edge-first in said direction with respect to the cable, the improvement comprising:

said first portion comprising low friction support means for reducing the drag on the cable during the relative movement, said first portion being in said direction from said cutting edge and closely adjacent thereto;

said second portion comprising low friction support means for reducing the drag on the cable during the relative movement, said second portion being spaced from said cutting edge in the reverse of said direction;

said cutting edge being inclined with respect to said passageway such that the part thereof adjacent the other side of the passageway is farther in said direction than is the part of the edge adjacent said one side of the passageway whereby as said relative movement occurs the object is wedged between said edge and said first portion.

2; in a device as set forth in claim 1, wherein said low friction support means each comprises a roller rotatably mounted on said frame for rotation about an axis transverse to the length of the object.

3. In a device as set forth in claim 2, wherein said frame is in theform of a sleeve having walls defining an interior chamber which is open at the ends of the sleeve, with one wall forming said third portion and the opposite wall forming said fourth portion, said knife and said means being within said chamber and between said walls, said sleeve having a slot extending between the ends thereof through which the object may be introduced into the sleeve, said knife and one of said means being between one end opening and the slot, the other of said means being between the other end opening and the slot. 4. In a device as set forth in claim 3, wherein said slot extends diagonally across one of said walls dividing said wall into two parts, said first portion and said knife being between one part and the opposite wall, said second portion being between said second part and said opposite wall.

' 5. [n a device as set forth in claim 1, wherein said passageway has a longitudinal axis which intersects said knife at a point, and wherein said frame includes a handle to facilitate grasping the device, said handle including a center and being positioned such that an acute angle is formed between said longitudinal axis and a line from said center to said point. I

6. In a hand-manipulated device for slitting an object, such as an electrical cable or the like, having first and second sides defining in cross section a predetermined depth and third and fourth sides defining in cross section a predetermined width and wherein the device has a frame, has portions defining a passageway for the cable which portions include first and second portions spaced apart approximately said predetermined depth as measured transversely of the passageway and third and fourth portions spaced apart approximately said predetermined width as measured transversely of the passageway, and has a knife with a cutting edge projecting into said passageway from the one side thereof at which said first portion is positioned and toward the other side thereof at which said second portion is positioned with the knife being between said third and fourth portions so that the knife slits the cable while the cable is grasped with one hand and the device is grasped by the other and a relative movement between the two is produced, which movement is longitu-' dinally of the object and in a direction such that the cutting edge moves in said direction with respect to the cable, the improvement comprising:

said frame being in the form of a sleeve having walls defining an interior chamber which is open at the ends of the sleeve, with one wall forming said third portion and the opposite wall forming said fourth portion, 5

said first portion being at one position along said passageway,

said second portion being at another position along said passageway with the other position being spaced longitudinally of the'passageway from the one position,

said knife being at a third position longitudinally of said passageway, which third position is between said first and second positions,

said cutting edge being inclined with respect to said passageway such that the part thereof adjacent the other side of the passageway is farther in said direction than is the part of the edge adjacent said one side of the passageway whereby as said relative movement occurs the object is wedged between said edge and said first portion.

7. in a device as set forth in claim 6, wherein said knife and said means are within said chamber'and between said walls, said sleeve having a slot extending between the ends thereof through which the object may be introduced into the sleeve, said knife and one of said means being between one end opening and the slot, the other of said means being between the other end opening and the slot.

8. in a device as set forth in claim 7, wherein said knife is between two of said walls and including a knife holdingblock at each side of the knife respectively between the knife and the adjacent wall, and a bolt between said two walls, said knife, and said blocks to clamp the knife between the blocks.

9. In a device as set forth in claim 6, wherein said passageway a longitudinal axis which intersects said knife at a point, and wherein said frame includes a handle to facilitate grasping the device, said handle including a center and being positioned such that an acute angle is formed between said longitudinal axis and a line from said center to said point.

10. in a hand-manipulated device for slitting an object, such as an electrical cable or the like, having first and second sides defining in cross section a predetermined depth and third and fourth sides defining in cross section a predetermined width and wherein the device has a frame, has portions defining a passageway for the cable which portions include first and second portions spaced apart approximately said predetermined depth as measured transversely of the passageway and third and fourth portions spaced apart approximately said predetermined width as measured transversely of the passageway, and has a knife with a cutting edge projecting into said passageway from the one side thereof at which said first portion is positioned and toward the other side thereof at which said second portion is positioned with the knife being between said third and fourth portions so that the knife slits the cable while the cable is grasped with one hand and the device is grasped by the other and a relative movement between the two is produced, which movement is longitudinally of the object and in a direction such that the cutting edge moves in said direction with respect to the cable, the improvement comprising:

said frame being in the form of a sleeve having walls defining an interior chamber which is open at the ends of the sleeve, with one wall forming said third portion and the opposite wall forming said fourth portion,

said knife and said means being within said chamber and between said walls, said sleeve having a slot extending between the ends thereof through which the object may be introduced into the sleeve, said knife and one of said means being between one end opening and the slot, the other of said means being between the other end opening and the slot.

11. In a device set forth in claim 10, wherein said knife is between two of said walls and including aknife holdingblock at each side of the knife respectively between the knife and the adjacent wall, and a bolt between said two walls, said knife, and said blocks to clamp the knife between the blocks. I

12. In a device as set forth in claim 10, wherein said slot has a width approximately equal to said predetermined depth.

13. A device for slotting an elongate object such as an electrical cable including a shell forming a receiving space open at its ends, and having a slot which opens the length of said space to permit the lateral entry of the object edge-first into the passageway; guide means on opposite sides of the space and slot and spaced apart lengthwise of the slot, means for pulling the device with one of the guide means leading the other, a knife located closely behind the leading guide means, guarded by the shell, and projecting into the receiving space but not into the path of lateral entry of the object into the receiving space through the slot, the flat side of the knife lying parallel to the length of the slot and the knife having a sharp cutting edge along the front edge of the knife terminating with a sharp point directed toward the object after its entry through the slot, the position of the means for pulling being such that reaction between pull thereon and a force restraining the object rearwardly of the device causes the point to penetrate the object, the slope of the cutting edge then being rearward from the point to urge the object against the forward guide means, said guide means and shell being constructed to position the object laterally for determining the path of the knife in the object during relative movement between the device and object longitudinally of the object. 

1. In a hand-manipulated device for slitting an elongate object, such as an electrical cable or the like, having first and second sides defining in cross section a predetermined depth and third and fourth sides defining in cross section a predetermined width and where in the device has a frame, has portions defining a passageway for the cable which portions include first and second portions spaced apart approximately said predetermined depth as measured transversely of the passageway and third and fourth portions spaced apart approximately said predetermined width as measured transversely of the passageway, and has a knife with a cutting edge projecting into said passageway from the one side thereof at which said first portion is positioned and toward the other side thereof at which said second portion is positioned with the knife being between said third and fourth portions so that the knife slits the cable while the cable is grasped with one hand and the device is grasped by the other and a relative movement between the two is produced, which movement is longitudinally of the object and in a direction such that the knife moves cutting-edge-first in said direction with respect to the cable, the improvement comprising: said first portion comprising low friction support means for reducing the drag on the cable during the relative movement, said first portion being in said direction from said cutting edge and closely adjacent thereto; said second portion comprising low friction support means for reducing the drag on the cable during the relative movement, said second portion being spaced from said cutting edge in the reverse of said direction; said cutting edge being inclined with respect to said passageway such that the part thereof adjacent the other side of the passageway is farther in said direction than is the part of the edge adjacent said one side of the passageway whereby as said relative movement occurs the object is wedged between said edge and said first portion.
 2. In a device as set forth in claim 1, wherein said low friction support means each comprises a roller rotatably mounted on said frame for rotation about an axis transverse to the length of the object.
 3. In a device as set forth in claim 2, wherein said frame is in the form of a sleeve having walls defining an interior chamber which is open at the ends of the sleeve, with one wall forming said third portion and the opposite wall forming said fourth portion, said knife and said means being within said chamber and between said walls, said sleeve having a slot extending between the ends thereof through which the object may be introduced into the sleeve, said knife and one of said means being between one end opening and the slot, the other of said means being between the other end opening and the slot.
 4. In a device as set forth in claim 3, wherein said slot extends diagonally across one of said walls dividing said wall into two parts, said first portion and said knife being between one part and the opposite wall, said second portion being between said second part and said opposite wall.
 5. In a device as set forth in claim 1, wherein said passageway has a longitudinal axis which intersects said knife at a point, and wherein said frame includes a handle to facilitate grasping the device, said handle including a center and being positioned such That an acute angle is formed between said longitudinal axis and a line from said center to said point.
 6. In a hand-manipulated device for slitting an object, such as an electrical cable or the like, having first and second sides defining in cross section a predetermined depth and third and fourth sides defining in cross section a predetermined width and wherein the device has a frame, has portions defining a passageway for the cable which portions include first and second portions spaced apart approximately said predetermined depth as measured transversely of the passageway and third and fourth portions spaced apart approximately said predetermined width as measured transversely of the passageway, and has a knife with a cutting edge projecting into said passageway from the one side thereof at which said first portion is positioned and toward the other side thereof at which said second portion is positioned with the knife being between said third and fourth portions so that the knife slits the cable while the cable is grasped with one hand and the device is grasped by the other and a relative movement between the two is produced, which movement is longitudinally of the object and in a direction such that the cutting edge moves in said direction with respect to the cable, the improvement comprising: said frame being in the form of a sleeve having walls defining an interior chamber which is open at the ends of the sleeve, with one wall forming said third portion and the opposite wall forming said fourth portion, said first portion being at one position along said passageway, said second portion being at another position along said passageway with the other position being spaced longitudinally of the passageway from the one position, said knife being at a third position longitudinally of said passageway, which third position is between said first and second positions, said cutting edge being inclined with respect to said passageway such that the part thereof adjacent the other side of the passageway is farther in said direction than is the part of the edge adjacent said one side of the passageway whereby as said relative movement occurs the object is wedged between said edge and said first portion.
 7. In a device as set forth in claim 6, wherein said knife and said means are within said chamber and between said walls, said sleeve having a slot extending between the ends thereof through which the object may be introduced into the sleeve, said knife and one of said means being between one end opening and the slot, the other of said means being between the other end opening and the slot.
 8. In a device as set forth in claim 7, wherein said knife is between two of said walls and including a knife holding block at each side of the knife respectively between the knife and the adjacent wall, and a bolt between said two walls, said knife, and said blocks to clamp the knife between the blocks.
 9. In a device as set forth in claim 6, wherein said passageway a longitudinal axis which intersects said knife at a point, and wherein said frame includes a handle to facilitate grasping the device, said handle including a center and being positioned such that an acute angle is formed between said longitudinal axis and a line from said center to said point.
 10. In a hand-manipulated device for slitting an object, such as an electrical cable or the like, having first and second sides defining in cross section a predetermined depth and third and fourth sides defining in cross section a predetermined width and wherein the device has a frame, has portions defining a passageway for the cable which portions include first and second portions spaced apart approximately said predetermined depth as measured transversely of the passageway and third and fourth portions spaced apart approximately said predetermined width as measured transversely of the passageway, and has a knife with a cutting edge projecting into said passageway from the one side thereof at which said First portion is positioned and toward the other side thereof at which said second portion is positioned with the knife being between said third and fourth portions so that the knife slits the cable while the cable is grasped with one hand and the device is grasped by the other and a relative movement between the two is produced, which movement is longitudinally of the object and in a direction such that the cutting edge moves in said direction with respect to the cable, the improvement comprising: said frame being in the form of a sleeve having walls defining an interior chamber which is open at the ends of the sleeve, with one wall forming said third portion and the opposite wall forming said fourth portion, said knife and said means being within said chamber and between said walls, said sleeve having a slot extending between the ends thereof through which the object may be introduced into the sleeve, said knife and one of said means being between one end opening and the slot, the other of said means being between the other end opening and the slot.
 11. In a device set forth in claim 10, wherein said knife is between two of said walls and including a knife holding block at each side of the knife respectively between the knife and the adjacent wall, and a bolt between said two walls, said knife, and said blocks to clamp the knife between the blocks.
 12. In a device as set forth in claim 10, wherein said slot has a width approximately equal to said predetermined depth.
 13. A device for slotting an elongate object such as an electrical cable including a shell forming a receiving space open at its ends, and having a slot which opens the length of said space to permit the lateral entry of the object edge-first into the passageway; guide means on opposite sides of the space and slot and spaced apart lengthwise of the slot, means for pulling the device with one of the guide means leading the other, a knife located closely behind the leading guide means, guarded by the shell, and projecting into the receiving space but not into the path of lateral entry of the object into the receiving space through the slot, the flat side of the knife lying parallel to the length of the slot and the knife having a sharp cutting edge along the front edge of the knife terminating with a sharp point directed toward the object after its entry through the slot, the position of the means for pulling being such that reaction between pull thereon and a force restraining the object rearwardly of the device causes the point to penetrate the object, the slope of the cutting edge then being rearward from the point to urge the object against the forward guide means, said guide means and shell being constructed to position the object laterally for determining the path of the knife in the object during relative movement between the device and object longitudinally of the object. 